Separation of ethyl acetate from azeotropic mixture of ethyl acetate and ethanol is of great significance in the industrial production of ethyl acetate. Current purification techniques include extractive distillation and azeotropic distillation, which are energy intensive. Under the guidance of crystal structure prediction, a template strategy was used to construct selective binding sites for solvent molecules in trigylamine macroring crystals. These crystals exhibit inherently high selectivity for intrinsic ethyl acetate, reasonable kinetics, and are expected to be used for practical dynamic separation in real life.

Ethyl acetate is an important chemical raw material and solvent. It is also a key volatile organic compound in the brewing industry and a marker of lung cancer. The separation and detection of ethyl acetate requires highly selective materials for ethyl acetate. Here, we report a trianglimine macrocyclic compound (TAMC) that selectively adsorbs ethyl acetate through the formation of solvates. Crystal structure prediction indicates that this is the lowest energy solvate structure available. The solvate leaves a metastable "templated" cavity after solvent removal. Adsorption and breakthrough experiments confirmed that TAMC has sufficient adsorption kinetics to separate an azeotropic mixture of ethyl acetate from ethanol, a challenging and energy-intensive industrial separation.

Ethyl acetate (EA) is the key solvent in chemical industry. It is also a key volatile organic compound (VOC) that can determine the flavor and quality of a beer or wine. EA is also a biomarker for early diagnosis of lung cancer. Fischer esterification (EtOH) of ethanol is the main industrial process for EA synthesis. Subsequent separation of EA and EtOH is difficult because they have similar boiling points (78.5 °C and 77.1 °C, respectively); In addition, EA and EtOH form an azeotropic mixture. Current purification technologies include extractive distillation, azeotropic distillation using ionic liquids, and membrane separation, but these can be inefficient and energy intensive. It is possible to find alternative separation processes based on selective adsorption that use microporous materials that can operate in atmospheric conditions. In addition to separation, porous materials with high selectivity for EA can also be used as adsorbents in thermal desorption techniques to quantify trace amounts (PPM) EA in gaseous mixtures.

Macrocyclic organic compounds have been extensively studied in solutions as hosts of various guest molecules, including organic molecules, metal cations, and nucleotides. Macrorings also show potential as solid porous media for selective adsorption of gases or vapors. For example, β -cyclodextrin (β-CD) has been shown to capture VOCs such as styrene, aniline and benzaldehyde from polluted air. It has been reported that cup -[4] -arene macrocyclic compounds with hydrophobic cavities can selectively adsorb volatile organic compounds such as toluene, benzene, nitrobenzene and phenol from aqueous solutions. We found that column [N] arene can be used to separate styrene from ethylbenzene and adsorb p-xylene from its structural isomers.